Into the Unknown: What Might a Combined Influenza/COVID-19 Season Look Like This Fall?

Where Did Influenza Go This Year?

Ask the average person whether it feels like we are starting to get out of the woods on COVID-19 and most everyone would respond in the affirmative, despite some worrying trends in vaccine hesitancy and hospitalizations of young adults. It sure feels like we’ve been hunkered down for quite a long time now. Remember the flu? It’s practically nonexistent this year. The latest data show substantially fewer than 1000 lab-confirmed cases, with only 1 pediatric death nationwide directly coded to the flu for the 2020-2021 season.¹ The CDC has chosen to track Pneumonia-Influenza-COVID-19 (PIC) as a bundle of coded conditions for death and will likely continue to do so. From the January 1, 2021, through June 12, 2021, there have been 256,915 PIC deaths.¹ In a normal year, between 6% and 8% of all deaths are from influenza- or pneumonia-coded illness; at our peak earlier this year, PIC produced more than 25% of our nation’s deaths.¹

Mitigating COVID-19 Spread has Taught Us Something (That We Already Knew) About Influenza

Social distancing, wearing masks, washing hands, and getting the flu vaccine are all great ways to avoid getting influenza, at least until another strain comes around. Of course, doing the same for COVID-19 clearly had the same effect, and the evidence supporting behavior-driven mitigation of spread is now overwhelming. There is some ongoing debate about the effectiveness of this year’s influenza match up against the advantage of these behavior changes, but together they are clearly successful in reducing the spread of influenza. Notably, Pacific Rim and East Asian countries have largely figured this out already, and mask wearing during outbreaks is commonplace in countries like South Korea and Japan.

Seasonal and Infectious, But Only One Remains Elusive (For Now)

I quite enjoyed not getting any symptoms or sickness from the flu this year, and I’d like to keep it that way. Unlike for COVID-19, we don’t get nearly perfect coverage and effectiveness rates in the 90%-plus range for the influenza vaccine.² Rather, we are generally quite happy with rates between 40% and 60%.³ Assuming we get to a manageable, steady state, or a low rate of COVID-19 with booster management, will influenza roar back? Or has COVID-19 changed our therapeutic prowess and social behaviors?

The More Powerful Influence: Lessons Learned or Vaccine Fatigue?

Habits are a powerful influence. We are more than 14 months now into handwashing, wearing masks, avoiding the other person walking down the aisle at the grocery store, and holding our breath. (Admit it. You’ve done it in an elevator.) These habits and front-of-mind awareness will persist. Will I wear a mask everywhere I go? Will I avoid live concerts? Doubtful. Will I get an influenza vaccination? Of course. But what’s the view from the non–health care professional? We still regularly fail to hit 50% of adults vaccinated against the flu most years.⁴ Will that rate go up or down? It’s so hard to predict: Will COVID-19 mitigation and behavior continue after case rates drop, and will flu again become the principal threat each fall?

Brazil, India, and the Realization That COVID-19 Isn't Going Away

Then there is the worldview. While we begin to have an embarrassment of abundance of vaccine supplies,⁵ much of the world is still struggling with COVID-19. India can’t keep up with cremations, while Brazil is still in denial.⁶ If the world’s rate of COVID-19 infections doesn’t come down, herd immunity will get harder as trade and international travel scream to move on. The cruise industry and the CDC are locked in a bitter battle,⁷ and airline CEOs are grappling with how to treat international travel differently than domestic travel⁸ as our own “bubble” now eclipses 60% vaccinated with at least 1 dose.⁹

Will Testing Take a Front Seat?

What if a basal rate of COVID-19 infections persists, despite widespread vaccine availability with near 100% effectiveness against severe disease and death,² especially in the face of an opening up of society that lets us experience a typical flu season? Well, lots of testing would result, one might surmise. Unlike spring allergies, where the differential between COVID-19 and sneezing is more distinct, flu and COVID-19 are remarkably similar in their presentation, although not necessarily in their treatment¹⁰—especially in light of oral agents for influenza versus some of the emerging treatment options for patients with COVID-19, with early but potentially progressive infections.¹¹ Testing for influenza with COVID-19 ruled out may become the new normal, for the sake of both patients and surveillance.

2022 Could Be Watershed Year If We Are Prepared, Keep Public Trust

It’s entirely possible for us to vaccinate most Americans against COVID-19; continue testing efforts; and sustain noninfringing, nonimposing, and easy-to-implement behavior change—and still have influenza vaccination rates above 50% this fall. With nearly half a million PIC deaths this year—and the 3 prior years producing roughly 100,000, 80,000, and 80,000 PIC deaths, respectively, inclusive of baseline pneumonia (and the earlier 2 having no COVID-19 deaths)¹—might we end up with far fewer overall PIC deaths next year and set a new baseline with our new behaviors and vaccine technologies? Or will we slide back into complacency? Much of that has to do with pharmacist-led preparedness, patient counseling, public communication, and action. Oh, and by the way, maybe now we’ll be better about promoting and administering pneumonia vaccines as well.

Troy Trygstad, PharmD, PhD, MBA, is vice president of pharmacy and provider partnerships for Community Care of North Carolina, which works collaboratively with more than 2000 medical practices to serve more than 1.6 million Medicaid, Medicare, commercially insured, and uninsured patients. He received his PharmD and MBA degrees from Drake University and a PhD in pharmaceutical outcomes and policy from the University of North Carolina. He also serves on the board of directors for the American Pharmacists Association Foundation and the Pharmacy Quality Alliance.

REFERENCES

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